Spoilers
I take back what I said. I'm not at least fifty percent sure, that Snape is indeed evil. Did you see the first part of the interview by Melissa and Emerson.
MA: OK, big big big book six question. Is Snape evil?
JKR: [Almost laughing] Well, you've read the book, what do you think?
ES: She's trying to make you say it categorically.
MA: Well, there are conspiracy theorists, and there are people who will claim -
JKR: Cling to some desperate hope [laughter] -
ES: Yes!
MA: Yes!
ES: Like certain shippers we know!
[All laugh]
JKR: Well, okay, I'm obviously - Harry-Snape is now as personal, if not more so, than Harry-Voldemort. I can't answer that question because it's a spoiler, isn't it, whatever I say, and obviously, it has such a huge impact on what will happen when they meet again that I can't. And let's face it, it's going to launch 10,000 theories and I'm going to get a big kick out of reading them so [laughs] I'm evil but I just like the theories, I love the theories.
ES: I know Dumbledore likes to see the good in people but he seems trusting almost to the point of recklessness sometimes.
[Laughter] Yes, I would agree. I would agree.
ES: How can someone so -
JKR: Intelligent -
ES: be so blind with regard to certain things?